Department of Molecular Life Sciences and Neuroscience Center Zurich, University of Zurich, Zurich, Switzerland.
Elife. 2021 Mar 2;10:e64767. doi: 10.7554/eLife.64767.
Axon navigation depends on the interactions between guidance molecules along the trajectory and specific receptors on the growth cone. However, our in vitro and in vivo studies on the role of Endoglycan demonstrate that in addition to specific guidance cue - receptor interactions, axon guidance depends on fine-tuning of cell-cell adhesion. Endoglycan, a sialomucin, plays a role in axon guidance in the central nervous system of chicken embryos, but it is neither an axon guidance cue nor a receptor. Rather, Endoglycan acts as a negative regulator of molecular interactions based on evidence from in vitro experiments demonstrating reduced adhesion of growth cones. In the absence of Endoglycan, commissural axons fail to properly navigate the midline of the spinal cord. Taken together, our in vivo and in vitro results support the hypothesis that Endoglycan acts as a negative regulator of cell-cell adhesion in commissural axon guidance.
轴突导航依赖于轨迹上的导向分子与生长锥上的特定受体之间的相互作用。然而,我们在体内和体外研究 Endoglycan 的作用表明,除了特定的导向线索-受体相互作用之外,轴突导向还依赖于细胞-细胞黏附的精细调节。Endoglycan 是一种唾液酸粘蛋白,在鸡胚中枢神经系统的轴突导向中发挥作用,但它既不是轴突导向线索,也不是受体。相反,Endoglycan 作为分子相互作用的负调节剂发挥作用,这一证据来自于体外实验,表明生长锥的黏附减少。在没有 Endoglycan 的情况下,连合轴突不能正确地穿越脊髓的中线。总之,我们的体内和体外结果支持这样一种假设,即 Endoglycan 作为连合轴突导向中细胞-细胞黏附的负调节剂发挥作用。